Known types of rectifier-distributor components in plate-type heat exchangers in the related art include a type provided with small holes or slits in a main pipe so as to evenly distribute a fluid to heat exchange channels between plates in the arrangement direction of the plates, and a type in which a pipe is reduced in diameter in the flowing direction so as to reduce the cross-sectional area of the channel (e.g., see Patent Literatures 1, 2, and 3).